diff --git a/packages/typescript-estree/src/create-program/shared.ts b/packages/typescript-estree/src/create-program/shared.ts
index b828478073e..8aceb204c47 100644
--- a/packages/typescript-estree/src/create-program/shared.ts
+++ b/packages/typescript-estree/src/create-program/shared.ts
@@ -32,7 +32,7 @@ const correctPathCasing = useCaseSensitiveFileNames
 
 function getCanonicalFileName(filePath: string): CanonicalPath {
   let normalized = path.normalize(filePath);
-  if (normalized.endsWith('/')) {
+  if (normalized.endsWith(path.sep)) {
     normalized = normalized.substr(0, normalized.length - 1);
   }
   return correctPathCasing(normalized) as CanonicalPath;